It is the cusp of World War I. The Austro-Hungarians and Germans have their Clankers, steam-driven iron machines loaded with guns and ammunition. The British Darwinists employ genetically fabricated animals as their weaponry. Their <I>Leviathan</I> is a whale airship, and the most masterful beast in the British fleet.<P> <P>Aleksandar Ferdinand, a Clanker, and Deryn Sharp, a Darwinist, are on opposite sides of the war. But their paths cross in the most unexpected way, taking them both aboard the Leviathan on a fantastical, around-the-world adventure&hellip;.One that will change both their lives forever.